Our primary goal is to help as many people as possible use and
contribute to Racket. We encourage anyone to develop any kind of
software, with any kind of license, using Racket.

We have chosen the LGPL as the license for Racket, which makes it
possible for people to create software with Racket, and to allow us
to build on existing libraries that use the LGPL, such as the Lightning
assembler and the GMP math library. The basic requirement of the LGPL
is that you make your changes to Racket available, and that you let
other people use your software with new versions of Racket.

Since the LGPL license that Racket uses was originally designed for C
programs, parts of it require some interpretation to apply to Racket in
detail. The following is how the Racket maintainers interpret the
license.

First, if you distribute your Racket application in source form or as
compiled bytecode files, the Racket license does not restrict you at
all.

Second, if you distribute your Racket application as compiled binary
generated by raco exe, there are no requirements placed on the
licensing of your software. However, the LGPL requires that you make
it possible to re-link your software with modified versions of
Racket. This means, basically, that you need to provide the compiled
bytecode files used to produce the compiled binary, if requested by
someone who got your software from you. Note that this does not
mean that your software has to be made open source, nor do you have
to give the source code to anyone, nor do you have to make the
compiled bytecode files available to the public or let other people
redistribute them. Furthermore, this is not revealing any more of
your source code than the raco exe format, since the bytecode is
embedded in an extractable way in the resulting executable.

We are, of course, not lawyers, and this should not be taken as legal
advice. However, we wanted to make it clear that Racket is an
appropriate building block for all kinds of software, and to clarify how
we view the license of Racket.